Vibration in my 2003 ZTW

[spiller]

Originally Posted by kkspeed

The weird thing about my vibration issue is that it is intermittent. Sometimes it goes away when the engine warm and runs real smooth. That is why I thought it was in the EGR system.

Secondly, the engine idles differently when the heater is set to defrost with the heat on.
I suspect the AC turns on automatically when the defroster is turned on to prevent the windows from fogging up.

I know that's wierd, but the material used in the motor mounts is a soft (hydraulic) substance. Does a great job of isolating and dampening vibration. Even if the engine is running poorly, the mounts in good condition, will stop all that vibration.
I believe as there are changes in its temperature, it probably expands a little leading to the vibration to go away. Also, as the engine changes its mixture, it'll change just how much vibration the mounts have to dampen. Mine would start up and vibration would be felt until warmed up AND then shut off and restarted.
Keep your focus on the mounts for now. If the RH mount had failed, it could easily have led to excessive stress on the other 2 mounts and a failure on either or both.

And yes, if your vehicle is equipped with A/C and you turn the air to Defrost, the A/C compressor will turn on. Even if you hit the A/C button on the panel to turn off the A/C light, I believe the A/C compressor still runs.

[spiller]

Originally Posted by kkspeed

The weird thing about my vibration issue is that it is intermittent. Sometimes it goes away when the engine warm and runs real smooth. That is why I thought it was in the EGR system.

Secondly, the engine idles differently when the heater is set to defrost with the heat on.
I suspect the AC turns on automatically when the defroster is turned on to prevent the windows from fogging up.

The intermittant issue does not entirely surprise. And yes the A/C compressor turns on with the defrost mode.

I don't know about aligning the RH mount/engine. I was just careful about the order I tightened the nuts and bolts. I did set the engine carefully when dropping the bolts thru the mount and into the frame.

The failure of the RH mount could have contributed to an early failure of either or both of the two other mounts.

Since good mounts should even isolate a bad running engine, I would confidently guess that your vibration is still the engine mounts.

Hey my earlier reply did post! (Sorry for the duplicate)

[iroc34]

Originally Posted by kkspeed

How do I check that the engine is aligned correctly?

Posted via FF Mobile

Well I don't think there is any measurement or any thing. I would try just sliding it fwd or back to see if it changes any thing.

[kkspeed]

Originally Posted by spiller

The intermittant issue does not entirely surprise. And yes the A/C compressor turns on with the defrost mode.

I don't know about aligning the RH mount/engine. I was just careful about the order I tightened the nuts and bolts. I did set the engine carefully when dropping the bolts thru the mount and into the frame.

The failure of the RH mount could have contributed to an early failure of either or both of the two other mounts.

Since good mounts should even isolate a bad running engine, I would confidently guess that your vibration is still the engine mounts.

Hey my earlier reply did post! (Sorry for the duplicate)

Thanks for the advice!

I'm going to change the dog-bone and transmission mounts.

Since I purchased a factory RH mount, is it worth it to spend the extra money on factory dog-bone and transmission mounts?

I heard bad things about Anchor mounts sold in chain auto part stores.

[spiller]

I went with NAPA mount. But that was not from any input about quality, but NAPA is far closer to me than the Dealer, and probably cheaper

[kkspeed]

Originally Posted by iroc34

Posted via FF Mobile

Well I don't think there is any measurement or any thing. I would try just sliding it fwd or back to see if it changes any thing.

It appears that you are correct.

I moved the metal bracket that the RH Hydralic Mount is bolted to back to the factory location (covered the paint wear marks in the frame) and the vibration is a lot better.

I guess the engine moved after I unbolted the RH Mount with a jack under the oil pan and I didn't move the bracket back to the factory location after I installed the new motor mount.

I'm still going to replace the dog-bone and transmission mounts for piece of mind.

Thank you to all the members for your help!

[iroc34]

Originally Posted by kkspeed

It appears that you are correct.

I moved the metal bracket that the RH Hydralic Mount is bolted to back to the factory location (covered the paint wear marks in the frame) and the vibration is a lot better.

I guess the engine moved after I unbolted the RH Mount with a jack under the oil pan and I didn't move the bracket back to the factory location after I installed the new motor mount.

I'm still going to replace the dog-bone and transmission mounts for piece of mind.

Thank you to all the members for your help!

Good news. Thanks for the update. Thats how we learn if our ideas work.

[iroc34]

Didnt move up the list. When I posted a comment last night.
Bump

[kkspeed]

PROBLEM SOLVED: Replaced the Dogbone and Transmission Mounts

No more Vibration!

Like I originally posted, I replaced the motor mount with a factory mount from the dealer and it helped, but I was still getting weird vibrations periodically.

Finally, I replaced the dogbone and transmission mounts and my ZTW feels new!
Very solid, quiet, with little vibration.

I guess it's best to replace the three mounts at the same time.

[chadr]

what year and models are compatible with my 2003 ztw mounts? I replaced mine but they are still in great shape so I'd like to sell them but I'm not certain how to list them. Here are the pictures of the mounts -

https://picasaweb.google.com/1023916...O3P1cqtkvfs8AE